Method and apparatus for servicing wells



4 Sheets-Sheet 1 July 7, 1970 o. R. HARRISON METHOD AND APPARATUS FORSERVICING WELLS Filed Dec. 11. 1968 N R0 w w 0s 0 O 2 W I L H R F E V R.N w 6 N ul G M B l I H 6 m o I N U T F 7 T E O m Y V S B R S E E E V S SN L E U A EV V L L O A M Y Hv R T R T E N N F W E O ,A O N C 5 4V A 7 Mm I Q Q I" 6- ll 2 m A H 7 2 7 4 4 ii 8 I!!! l 2 5 5 /I. ll .I. 9 k 2 Wi Juiy 7, 1970 o. R. HARRISON 3,519,078

METHOD AND APPARATUS FOR SERVICING WELLS Filed Dec. 11, 1968 4Sheets-Sheet 2 FIG. 3.

now-um:

FLEXIBLE TUBING 4| I; i H OCEAN FLOOR I H 25 g H a? "*SAFETY VALVES l 23,1 4 L L BOREHOLE l/ H 1 ll u |2 15 -44 H43 1; WELL TOOL 40 ll L f E L1.

DOWN-HOLE MASTER VALVES INVENTOR.

OTTO R. HARRISON, BY a 3 ATTO EY.

July 7, 1970 o. R. HARRISON METHOD AND APPARATUS FOR SERVICING WELLS 4Sheets-$heet 5 Filed Dec. 11, 1968 PUMP DOWN TOOL FOR l2 INVENTOR.

O TTO R- HARR ISON,

FIG. 5

July 7, 1970 o. R. HARRISON METHOD AND APPARATUS FOR SERVICING WELLS 4Sheets-Sheet 4 Filed Dec. 11, 1968 AT RNEY United States Patent3,519,078 METHOD AND APPARATUS FOR SERVICING WELLS Otto R. Harrison,Houston, Tex., assignor to Esso Production Research Company Filed Dec.11, 1968, Ser. No. 782,877 Int. Cl. E21b 7/12, 23/00 U.S. Cl. 166313 16Claims ABSTRACT OF THE DISCLOSURE Method and apparatus are provided forservicing wells involving a plurality of pipe strings of difierent sizesarranged in a well which curvedly connect to a common fiowline having ahorizontal and vertical component such that the pipe strings areconnected in order of increasing sizes with the largest connected lastat the highest point of the sloping fiowline so a properly sized welltool may enter a selected one of the pipe strings for operation therein;for example, to open or close a valve which may fluidly interconnect thepipe string to a service pipe string to provide a fluid circulationpath.

BACKGROUND OF THE INVENTION Field of the invention The present inventionis directed to servicing of wells. More particularly, the invention isdirected to servicing a well having a plurality of pipe strings arrangedtherein which may be fluidly connected adjacent their lower ends to aservice string. In its more specific aspects, the invention is concernedwith method and apparatus for utilizing through fiowline techniques forrunning of tools, and the like, in wells, and is particularly adapted touse of such techniques in submarine wells, and the like.

Description of the prior art It is known to perform operations in wellsparticularly submarine wells using the so-called through fiowlinetechnique wherein well tools are pumped into the wells through aseparate fiowline to each well. It is also known to interconnect a pipestring in a well to a service string to provide a fluid circulation pathto allow well servicing operations to be performed. All such operations,however, required heretofore one service string for each well SUMMARY OFTHE INVENTION The present invention may be briefly described andsummarized as involving a method of servicing a well having a pluralityof pipe strings which are curvedly interconnected at the Wellhead to acommon fiowline at least a portion of which has a horizontal componentin which a well tool is introduced into a common fiowline and movedtherethrough into a selected one of the pipe strings. The well tool maybe moved through the flowline by pumping fluid against the Well tool orby attaching the well tool to an elongated tubular member on a reel andforcing the tubular member into the fiowline by exteriorally appliedmechanical force on the tubular member. After the well tool is in theselected pipe string,

3,519,078 Patented July 7, 1970 ice it may there be operated, forexample, to open a valve, register pressure, log the well, or performany one or more of the multitudinous operations performed in wells withsuch tools.

The invention also involves apparatus which may be briefly described andsummarized as comprising a plurality of pipe strings in a well which areof different sizes and which are curvedly connected at their upper endsto a common fiowline, each of the pipe strings being connected in theorder of increasing size to the fiowline which has a horizontal andvertical component to provide an upward slope with the highest point atthe entrance of the largest pipe string. A service string may beconnected selectively to the lower ends of the several pipe stringsthrough selectively openable and closeable valve means which may bemovably or fixedly arranged in the pipe strings as desired.

BRIEF DESCRIPTION OF THE DRAWING The invention will be further describedand illustrated by reference to the drawing in which:

FIG. 1 is a schematic illustration in section of a quadruple completionin which the four pipe strings are connected to a service line;

FIG. 2 is a cross-sectional view of FIG. 1, showing pattern ofarrangement of the pipe strings in an earth borehole;

FIG. 3 is a cross-sectional view of a similar embodiment to FIG. 1wherein the four pipe strings are not interconnected adjacent theirlower ends;

FIG. 4 is a sectional view similar to FIG. 2;

FIGS. 5 and 5A illustrate the connection of one of the curved well pipesto the fiowline;

FIG. 6 is a modification of FIGS. 1 and 3 wherein the quadruplecompletion is connected to two fiowlines;

FIG. 6-A is a modification of FIG. 6; and FIG. 7 illustrates apparatusfor introducing well tools into the fiowline.

DESCRIPTION OF THE PREFERRED EMBODMENTS Referring now to the drawingillustrating the preferred mode and embodiments and particularly toFIGS. 1 and 2, numeral 11 designates a well bore drilled in the earthsurface and which suitably may be a submarine well. Arranged in the wellbore 11 is a plurality of pipe strings 12, 13, 14, and 15 which arecurvedly interconnected at their upper ends to a common fiowline 16 andare interconnected adjacent their lower ends to a service line 17. Forpurposes of clarity and convenience, in FIG. 1 the interconnecting means18 between service line 17 and line 12 and interconnection means 13between service line 17 and line 13 and interconnection means 20 betweenservice line 17 and line 14 and interconnecting means 21 between serviceline 17 and line 15 are exaggerated, but are shown in closerrelationship in FIG. 2.

Lines 12, 13, 14, and 15 are all suitably equipped respectively withsafety valves 22, 23, 24 and 25 and with downhole in line master safetyvalves 26, 27, 28, 29, 30, 31, 32, and 33. Valves 22, 23, 24, and 25 maybe valves of the type illustrated on page 3840 in the 1966-67 issue ofthe Composite Catalog. Valves 26 to 29 and 30 to 33, inclusive, areidentical and serve as back-up valves and the same purpose of the dualmaster valve system on a conventional Christmas tree and are availableon the market. Such a valve is illustrated on page 1124 of theabove-mentioned catalog. Arranged in the fiowline 16 and shown enteringthe line 14 is a suitable well tool 34 which may be a free tubularmember provided with a propelling means such as one or more pistons 35for propelling same into a selected one of the tubing strings 12, 13,14, and 15. In this particular invention, the well tool 34 is enteringthe string 14 and it is suitably sized so that it has a slightly lessdiameter than the diameter of string 14- but a greater diameter thanstrings 12 and 13; thus, the well tool 34 may enter the string 14 butwill not enter the strings 13 and 12. While the well tool 34 would alsoenter the string 15 since it is of smaller size than the string 15, thewell tool 34 enters selectively the desired pipe string by having theseveral pipe strings arranged in the order of increasing size as theyare joined to the flowline.

Referring now to FIGS. 3 and 4 where identical numerals designateidentical parts, it will be seen that the only difference between FIGS.1 and 3 is that the pipe strings 12, 13, 14, and 15 are notinterconnected adjacent their lower ends and also there is no servicestring provided. In this particular instance, a well tool is shown inthe pipe string 13 connected to a tubing 41 whiclextends to a reel andinjection means at the surface which will be described furtherhereinafter.

FIGS. 5 and 5-A illustrate one means for interconnecting the curved pipesections to the straight section of flowline. As shown, pipe 12intersects the under side of flowline 16 so as to provide a trough orentry slot 12a which has the same inside diameter as pipe 12. Thisprovides an area of suificient length to allow a well tool sized forpipe 12 to drop down in the trough and insure proper entry into pipe 12,as illustrated in FIG. 5-A. The dotted circles also shown in FIG. 5Aillustrate larger tools and how they would by-pass the tubing or pipe12.

Referring now to FIG. 6, the upper ends of pipe strings 12, 13, 14, and15 are connected to the flowline 16 as shown and by means ofY-connections 42, 43, 44, and 45 to a second flowline 46. By virtue ofthis embodiment, to provide additional flexibility when dual, triple,quadruple, pentuple or greater number of completions are made in onewell, a production flowline system may be used which requires identicalflowlines installed in parallel as shown on each pipe string 12, 13, 14,and 15 joined to both flowlines 16 and 46 by Y-connections. Thisembodiment allows any one producing pipe string to be plugged such as bya plug 47 shown entering string 15 and serviced without interruptingproduction from the other producing pipe strings. Of course, the plug 47may be seated in a suitable landing nipple and the like as desired. Anyone or more of the several pipe strings or flowline 46 may be plugged asshown. The connection illustrated in FIG. 6-A provides for theintersection of the two pipes 15 and 45a to be lower on the verticalsection of 15 than that shown in FIG. 6.

This type of completion allows logging, perforating, servicing, such asfracturing, acidizing and other services and completion of wells to beperformed from a production platform such as 50 which may be locatedmany miles way, for example, three miles away; thus, as shown in FIG. 7,the production platform 50 is suitably supported on water bottom 51which suitably may be the ocean floor with platform 50 above the watersurface 52, the platform 50 being carried and supported by structuralmembers 52. Arranged on the structural members 52 is a suitable rail 54on which a flowline riser 55 is installed such as in accordance with theteachings in the Walvoord Patent US. 3,226,728 issued Dec. 28, 1965.Thus, a flowline riser 55 connects to the flowline 16 and thereby to theservice lines 12, 13, 14, and 15 in the well 11.

In accordance with the present invention, the tubular member such as 41carrying the tool 40 as shown in FIG. 3 may be injected into flowline 16and into a selected one of the pipe strings 12, 13, 14, and 15 byintroducing same from a pipe reel and injection means such as 56arranged on the platform 50. The method and a suitable apparatus forintroducing the tubular member 41 are described in the McStravick PatentUS. 3,116,793 issued Jan. 7, 1964. Also, the tubular member 41 may beintro- 4 duced from apipe reel by introducing fluid pressure against thelower end of it such as against one or more pistons, and the like, topropel the tubular member 41 and its well tool into the selected pipestring.

Other well tools such as 34 are gun perforators, logging tools, sondes,bottom hole pressure devices, and the like, may be propelled into aselected one of the pipe strings by introducing it into the upper end offlowline 16 and riser 55 by a suitable lubricator or injection barrel 57provided with valves 58 and 59. The tool is introduced into the end 60and then fluid pressure introduced into the injection barrel 57 throughline 61 controlled by valve 62, the line 61 being connected to asuitable pumping means not shown. The injection barrel 57 may beconnected by branch line 63, controlled by valve 64 to storage 65 forreturn of fluid through a service line such as 17 illustrated in FIG. 1.The production platform 50, although shown with a pipe reel andinjection barrel, the storage means and other described apparatus willbe understood to include all suitable equipment for introducing toolsand propelling same through and into the several pipe strings as hasbeen described.

In the several embodiments described with respect to the several figuresof the drawing, it will be clear that the curved connections of pipestrings to the flowlines present a smooth entrance for well toolstraveling up the incline of the flowline such that the well tool willenter the selected pipe string. In short, the well tools must beproperly sized to enter the proper pipe string and the well tools travelthrough the flowline on the bottom inner surface thereof to enter theselected pipe string.

The flowline has at least a portion of its length horizontal and whereit is connected to the several pipe strings it has both a horizontal andvertical component such that an upwardly extending slope is presentedhaving its highest point at the entrance of the largest pipe string, itbeing remembered that the several pipe strings are connected to theflowline such as 16 in the order of increasing size with the smallestpipe string being connected first and the next larger and so on.

The present invention is quite advantageous and useful particularly inunderwater wells in reducing cost and providing for simplicity ofoperation in completions where a casing may be dispensed with. Only oneflowline and a reduced number of flowlines is necessary and completionand servicing operations may be performed from a remote location such ason shore, at a production or other servicing platform, or from afloating vessel as may be desired.

The several pipe strings such as illustrated in FIGS. 1 and 3 may beconnected together by interconnection means 18 to 21, inclusive, to aservice line 17 as shown in FIG. 1, and the service line selectivelyconnected to a particular pipe string by suitable valve means. Suchvalve means are well known in the art and a description of same may befound in the 1964-65 issue of the Composite Catalog, pages 3669 and3675. Likewise, in the Composite Catalog supra, the operation ofsuitable side doors for submarine completions are illustrated at page3634.

The well tools of the present invention may be used to open and closesuch valves selectively, and it is within the contemplation of thepresent invention that the well tools may be operated in the selectedpipe string after running it. It is also contemplated that the welltools may comprise a gun perforator, a logging tool, and the like, andsuch tools may also be operated remotely in accordance with the presentinvention.

The nature and objects of the present invention having been completelydescribed and illustrated and the best mode and embodiments contemplatedset forth what I wish to claim as new and useful and secure by LettersPatent is: p j

1. A method of servicing a well having a plurality of pipe stringsarranged therein in which said pipe strings are curvedly interconnectedat the wellhead to, and in fluid communication with a common flowline,at least a portion of the length of said flowline having a horizontalcomponent, which comprises:

introducing a well tool into said common flowline; and

moving said well tool through said flowline into a selected one of saidpipe strings.

2. A method in accordance with claim 1 in which the well tool isintroduced into said selected pipe string by pumping fluid into saidflowline after introducing said well tool.

3. A method in accordance with claim 1 in which the well tool isintroduced into said selected pipe string by connecting said Well toolto the end of a tubing string extending to a reel and propelling saidtubing string through said flowline and into said selected one of saidpipe strings.

4. A method in accordance with claim 3 in which the tubing string ispropelled by mechanical force exerted against said tubing stringexteriorly of said flowline.

5. A method in accordance with claim 3 in which the tubing string ispropelled by fluid pressure exerted against said tubing string as itmoves through said flowline and said selected one of said pipe strings.

6. A method in accordance with claim 1 in which said Well tool isoperated in said selected one of said pipe strings.

7. A method in accordance with claim 1 in which the common flowline hasa horizontal and vertical component at the point of connection to saidpipe strings such that said well tool is moved upwardly through saidflowline on the bottom inner surface thereof to enter said selected oneof said pipe strings.

8. A method in accordance with claim 7 in which each of said pipestrings is of a different size and is connected to the flowline in theorder of increasing sizes and said well tool is of a size selected toenter the first of said pipe strings having a size at least greater thanthe size of the well tool and less than the size of the next succeedingpipe string.

9. A method in accordance with claim 1 in which said pipe strings areeach selectively fluidly connected adjacent their lower ends to aservice pipe string.

10. Apparatus for use in servicing Wells which comprises:

a plurality of pipe strings in a well;

each of said pipe strings being of different diameter;

a flowline;

each of said pipe strings being curved at its upper end and connected tosaid flowline in the order of increasing diameter;

said flowline having a horizontal and vertical component to provide anupward slope with the highest point at the entrance of the largestdiameter pipe string and said pipe strings being curved to meet theflowline and provide a smooth entrance to said pipe strings.

11. Apparatus in accordance with claim 10 comprising three pipe strings.

12. Apparatus in accordance with claim 10 comprising four pipe strings.

13. Apparatus in accordance with claim 10 provided with:

(a) a service pipe string;

(b) means fluidly connecting each of said plurality of pipe strings tosaid service pipe string; and

(c) selectively openable and closeable valve means in at least saidselected one of said pipe strings to open and close a selected one ofsaid fluid connecting means.

14. Apparatus in accordance with claim 13 in which the valve means ismovably arranged in at least said selected one of said pipe strings.

15. Apparatus in accordance with claim 13 in which the valve means isfixedly arranged in at least said selected one of said pipe strings.

16. Apparatus in accordance With claim 10 compris ing four pipe stringsin which a second flowline is connected to each of said pipe stringsthrough a Y-connection.

References Cited UNITED STATES PATENTS 3,136,363 6/1964 Yetman et al.166-91 3,363,693 1/1968 Bohlmann et al. 166313 3,367,421 2/1968 Raulins166153 3,381,753 5/1968 Fredd 166-154 X 3,396,789 8/1968 Dean 166.53,422,895 1/1969 Koonce.

3,444,927 5/ 1969 Childers et al. 166.5

STEPHEN J. NOROSAD, Primary Examiner I. A. CALVERT, Assistant ExaminerUS. Cl. X.R. 166-.5, 153

